Flame resistant organic textiles and method of production



- polymers.

1 FLAME RESISTANT-ORGANIc-mnxrmns AND METHOD oEPRoDUGrloN v ""lwilsoa ne. Reeves", VLeon Reliance,nnaGeorgLfDrke,

Jr., New6rleans;--La:,- ssignors 'tuV the United States of America as represented'by the Secretary of Agriculture A'No' Drawing. li0.riginalapplication June 5', i1.956,4-Serial A non-exclusive, irrevg'n'cable,` royalty-free license in invention herein describedgtliroughout the World for all purposes ofthe United States Government, with the'power to grant sublicenses forsuchpurposes, isfj'hereby-granted 'to theGOVernmentioff the United States of America.

This invention relates to new Aphosphorus.and-.nitrogen containing polymers, processesnfor theirfproductionfand Y, processes of employing thesepolymers.intheameproofing of certain organic fibrous materials.

This application is a division of application-Serial No. 589,563, led June 5,"1956.

V-ln rgeneral, .this invention'relat'es to'polymers "capable ...of being producedtby -the reaction of 4a l-aziridinylphos- .A-pliine` oxideorsuliide -(e. gea compound thatfcontainsat least two -1-aziridinyl4 groups,

- attached'to pentavalentsphosphorus), with 'an amino 'compound having with a pluralityofradicals selected. from F'ffthegroup consisting'of VHand CHZOHattached to-the ftrivalentnitrogen'atomsgfand the-processes of-V reducing the combustibility of hydrophilic brous--organicimaterials.

We have discovered thatcompounds that contain at i i vleast two l-aziridinyl groups attached to pentavalent phosphoru's atoms react with amino compounds to produce 4 Such polymers contain the reoccuring connecting structures las is Van amino radical.

The VVpolymers can be produced inf'the form-of solid synthetic resins. They caribe deposited on the surfaces and/or in therinterstices of-hydrophilicbrous Aorganic materials, i. e., organic materials which absorb or adsorb -ing structure:

' i X-vrIL-X United. States Patent ice and where Z is oxygen .or.s`1ilfur. aziridinylv-compounds can be prepared bysbstantiallyanyof the known Vprocesses for producing /such compounds. -In general, .they are vprepared by reacting ethylenimine withy thel corresponding phosphorus halide.

a The Ypreparation `of .tris- (l-aziridinyl)phosphine: oxide t [(CH2)2N]3PO, has been -desribedgbyfBestian andcoworkers-[Bestian etal., Ann. .566, 210-2'44.(l950)].

illustrative-examples ofV suitable amino compounds inf clude: V l(.1) .organicamino compoundsfsuchasurea and urea derivatives like methylol ureas,ralkylated-methylol ,.ureas, melamine and melamine derivatives like methylol melamines, alkylated methylol .-me1amines, ,alkyljsuhstituted melamines such asstearylmelamine, (2) vvaliphatic amines such as ethylamine, Aethylenediamine 'and :cetylamine,l (3) amides suclijas. formamide, butyramide, and acrylamide; (4) inorganic amines such as ammonia, hydrazine and hydroxylaniin; (5) arylamines such as phenylenediamine; .1 and .'aniline;1-, (6) .peptide containing ...materials such vas dispersed Sproteins, wool, leather v and the like.

Polymers provided bythis invention -can be produced .in acidic, neutral; and alkalinefconditions. They canfrbe produced inthe form ofliquids or-solids andxcan-f-be 'molded by .the 'conventionaltechniques of molding V'tlermosetting resins. Tnesepolymers are -valuable materials Yfor useV in Ythe Yproduction ofzz moldedesynthetic articles, `v`such asf-buttons,-electrical insulatorsfand the like; syn- Y resins; and textile treating resins. Y Y ing compounds also react with protein-containing'subthetic coatings such as-protective coatings, and `paints and the'like having reduced ammability; paper vtreating The aziridine'containstances toproduce modified polymers with new andseful properties, such as for`example wool which is made dimensionally stable.

The'polymersprovided by this invention arevpreferably prepared by gently heating an aqueous solution ofthe aziridinyl phosphine oxide or sulfide and the amino 4comuniform suspension or dispersion, of the monomeric "comt pounds, or the partially polymeriz'ed `monomers vfc'irr'ried pound until polymerization occurs. The'preferr'edfrelative amounts of aziridinyl compound and amino compound used to polymerize can be calculated by conven- `tional methods by assuming that: (l) for eachl az'iridinyl group present in thecompound, theiunctionality isone ('e. g. if two aziridinyl groupsV arepresent, thefunctionality Vis, two), (2) fthat the functionality'of the amino *compound is Vequal to the sum of -H and V---CH2OH groups attached to 'trivalent'nitrogem The combustibility of`organic brous materials canlbe reduced in accordance with this invention by impregnating the fibrous materials with an aqueous solution, or

by reacting the monomeric. compounds until partial polymerization 'occurs' and curing`the impregnated materials at theiternperatures conventionally used for curing-iibrous organic materials.

Surface active agents,'water repellents, and othertextile treating agentsmay be `incorporated :into Vthe-aqueousA or vemulsion treating mediato modify the treatedA textiles.

Surface active softeningagents1 improve'tear strength? of cotton and rayon fabrics.

- t Eataented 4 l-having 1958 that-was soluble in hot water.

The process'of this invention can .be used to reduceY the combustibility of substantially any hydrophilic fibrous l material such as cotton, rayon such as viscose rayon, ramie, jute, wool, paper, cardboard and the like materials which can be impregnated with a liquid and dried or cured. Y

Where a textile is being impregnated, it is of advantage to remove excess impregnating liquor by passing the tex-E.

two days.

tile through squeeze rolls prior to drying or curing the impregnated textile. It isfalso advantageous todry the textile at about 70 to 110 C. before it is cured at a temperature of from about 100 to 170 C.

The degreeof flame resistance imparted to a textile ant, and rot and mildew resistant; the effects of the treatment are permanenfand resistant to laundering, dry

^ cleaning, and boiling alkali solutions; cellulosic textile materials retain a very high percentage of their tear and tensile strength; treated textiles are made highly flame resistant withrelatively small amounts of the phosphorus and nitrogen'containing polymers.

The following examples are illustrative Yof details of the invention. The terms parts or percent refer to parts or percent by weight.` The term APO refers to tris(l-aziridinyUphosphine oxide and the term APS re-` fers to tris(laziridinyl)phosphine sulde.

Example 1 Ethylenedem-ne with VPO.--Eight ounce cotton sateen fabric was padded in an aqueous solution containing 15 parts of APO, 5.2 parts of ethylenediamine and v 47.1 parts of water (onermole of ethylenediamine per The mole of APO). The pH of the solution was 12.1. wet fabric was dried for 15 minutes at 90C., then cured 5 minutes at 140 C. After the fabricwas thoroughly washed and air dried it contained 13.4% resin. The fabric contained both phosphorus and nitrogen and was highly flame resistant. The-hand and strength of the fabric wasV substantially the same as before the resin was put in it. a

A similar piece of fabricwas treated exactly as above except that the solution contained 11.8 parts of APO, 6.3 parts lof ethylenediamine and 42.2 parts of water (1.5 moles of ethylenediamine per mole of APO). The treated fabric contained 13.5% resin and was highly flame resistant. It was also strong, had a good hand and resisted shrinkage when laundered. The fabric remained ame resistant even after'boiling 3 hours in a solution ,YV

containing soap and sodium carbonate. Y

Example 2 Y 1,2-propylenedamne with'APO.-Cotton fabric was padded with a solution containing 10 parts of APO, 6.5

parts 1,2-propylenediamine and 38.5 Vparts of water. The wet fabric was dried 15 minutes at 90 C. then heated 5 minutes at 140 C. After washing in hot water and air drying, the fabric contained 9.3%V resin add-on and YExample 3 i Hydrazznewz'th APO.-Fabric was treated exactly as described in Example, 2 except that the treating solution contained 15.0 partsV APO, 4.2 parts of hydrazine and 44.8 parts of water. The treated fabric contained 9.3% resin after washingand drying; It was highly ame resistant. Y Y

The treating solution remaining after fthe fabric was treated was heated on a-steam bath to distill off much oi the water. A light brown colored polymer formed Example 4 Hydrazin'e with `APO.-A solution was preparedcontaining 5 parts APO,V 1.4 parts hydrazine, and'2.6 parts Y Y The solution was placed in an ice bath for two .Y hours and then allowed `to stand at room temperature for f An'almost colorless exible polymer` was f formed; It was cured byV heating for Ytwo. hours onfaf Water.

steam cone. Theameresistant polymer was insolubleV in boiling water vand acetone.

Ethylenediamne with APO.-A solutionwas prepared t. containing 5 parts APO and 2.6 parts ethylen'ediamine.v It was allowedrto stand Vat room temperature for 22'hours a l and then heated one hour at C. A clear,v hard color-` less polymer was forme'di'nsoluble-in boiling water,'acetone, and benzene. was obtained by furthercuring for 15n1inutesV at'115 C. and 10 minutesrat 140 C g,

i i Example 6 Methylol'melamne with APS-'4A solution containing'v 7.5 parts APS, 7.5 partsV of trimethyloljmelaminey and 35 parts of water (pH was 7.2) was heated for one hour on a steam cone, then spread out to a VthinV layerVv (about 3 mm. thick) and'.l heated at 140 C. for 5 minutesfA hard polymer Vformed that,V was insoluble in hot water.

The polymerrcontained phosphorus `and nitrogen; Y

Y Example7 Y V Ethanolamine .with PS.-A solution containing 15 parts of APS, Y 1.'6`\parts.of ethanolamineand 26.4 parts of' water was heated 30 minutes overrs'team`(temperature was approximately 75 'C.-)LV Then the Vviscous solution Y was lspread out into a thin layer (about 2-'5 mm. thick) and heated for 5 minutes at 140 C. A clear, practically.' It was Very tough and pliable. V The polymer was insoluble in water, ethanol and acetone. -V itwould not support a'ame when attempts were made',V v

colorless polymer formed.

to ignite it with a match.` i A similar polymer was ,made by heating 5 parts of -APS and V1.6 parts of ethanolamine (without solvent) for 10V Y minutesatC. .Y Y Example 8 Y Ammonia with APS.-19 parts of APS were'dissolved in 4-3 parts of warm water, then 12 parts of concentratedV ammonium'hydroxide (37% NH4OH)'werre added. The!V 1 solution was'stirred for 10 minutesand vthen'part'of'it was used to treat cotton fabric by padding, and drying. at 100 C. for 30 minutes. The other part was placedV upon a steam cone and heated. After about 30 minutes an oily Vphase began to drop out. Y continued for a total of 1.5 hours then the upper aqueous phase was decanted. The lower oily phase was cooled` to about 25 C. at which temperature it became more cured resin did not become discolored when. heated `at for 40 minutes. The resinfcontained phosphorus i and nitrogen and-was highly ame resistant.

Example 9 Urea with APO.-An aqueous'solution was preparedV Y by dissolving 15 parts of APO and 7.8 parts of `urea -in 53 parts of water.

Part of the solution was used to treat 8 oz. cotton Sateen fabric by padding, drying 15 minutes at 85 C., and curing 8 minutesV at 140 C. The treated fabricwasf flame resistant (it passed the 90 angle strip ame test); and remained ame resistant after a vigorous wash with soap and water. Y Y l Another part of the solution described above was i Y A harder polymer Vwas 1 formed by furthercuring for 2O minutes at 105 f A .harder llameV resistant Vpolymer The heating wasV It was essentially insoluble in water but was 1 soluble in concentrtaed and dilute aceticfacid. Some of the Aviscous oil was converted intoa hard clear resin by heating a thin lm of it for 10 minutes at 120 C. The

The pH of this solution Vwas l7.6.

placed in a watch glass and heated over a steam con'e.

A hard rubbery polymer formed after about one hour on the steam cone. Upon curing this polymer in an oven at 110 C. for 30 minutes it became very hard and tough. A piece about 1 mm. thick and about 25 mm. wide was Very diiicult to break with the hands; Some of this slightly amber colored tough polymer was heated an additional hour at 140 C.; this heating did not cause any apparent changes to the polymer. It was ame resistant.

Example Phenylenedamne with APS.-A solution was prepared by dissolving 30 parts of APS and 26 parts of paradiphenylenediamine in 200 parts of warm water. The solution was heated for 30 minutes on a steam bath then a portion of the solution was-placed in the bottom of a glass container so that the depth of the solution was about 3 mm. When the thin layer was heated for 5 minutes at 130 C., it formed a very hard brittle resin. It was insoluble in water and in benzene. The resin was highly flame resistant.

Example 11 Monostearyl melamine with APS.-A solution was prepared by dissolving 3 parts of APS and 13.4 parts of monostearyl melamine in 40 parts of benzene. The solution was heated minutes on a steam bath and then one hour at 140 C. in a forced draft oven. An amber colored resin formed. It was insoluble in hot benzene. The resin was very tough and exible. It would not supv port combustion.

group consisting of poly (1-aziridinyl) phosphine oxides and suldes and an amino compound having at least two members of the group consisting of H- and -CHZOH attached to a trivalent nitrogen atom, an'd heating the impregnated material to cause the phosphorus compound and the amino compoundto form a flame resistant condensation polymer in the fibrous material.

3. A flame proof hydrophilic fibrous organic material produced by the process of claim 2.

4. A process for ameproong hydrophilic fibrous organic material which comprises impregnating said hy-y drophilic fibrous organic material with a homogeneous liquid composition comprising a partial polymerization product obtained by warming a mixture of a phosphorus compound selected from the group consisting 'of poly (l-aziridinyl) phosphine oxides and suliides and an amino compound having at least two members of the group consisting of H- and -CHZOH attached to a trivaleut nitrogen atom, and heating the impregnated material to complete the polymerization an'd form a flame resistant condensation polymer in the brous material.

5. A process of reducing the ammability of a cellulosic textile material which comprises impregnating the material with a solution containing tris(1aziridinyl) phosphine sulde and urea, drying the impregnated material,A and then heating it to about from to 160 C. for about from 2 to 10 minutes, using the longer time p References Cited in the le of this patent t UNITED STATES PATENTS Parker et al. Aug. 12, 1952 2,654,738 Lecher et al. Oct. 6, 1953 2,672,459 Kuh et al. Mar. 16, 1954 2,781,281 Berger Feb. 12, 1957 

1. A PROCESS OF REDUCING THE FLAMMABILITY OF A CELLULOSIC TEXTILE MATERIAL WHICH COMPRISES IMPREGNATING THE MATERIAL WITH A SOLUTION CONTAINING TRIS(I-AZIRIDINYL) PHOSPHINE OXIDE AND UREA, DRYING THE IMPREGNATED MATERIAL AND THEN IT TO ABOUT FROM 100 TO 160*C. FOR ABOUT FROM 2 TO 10 MINUTES, USING THE LONGER TIME WITH THE LOWER TEMPERATURE. 